Clinical Results for Minimally Invasive Locked Plating of Proximal Humerus Fractures

Objectives: To describe the minimally invasive treatment of fractures of the proximal humerus using the Non-Contact-Bridging (NCB) plate. The system allows secondary locking of screws to the plate with a locking cap and polyaxial (30° radius) screw placement. Design: Prospective cohort study. Setting: University Level I trauma center. Patients: Fifty-four patients with unstable fractures of the proximal humerus. Intervention: Minimal anterolateral acromial approach to the proximal humerus, percutaneous fracture reduction, and minimally invasive application of the NCB plate. Main Outcome Measurements: Constant Score and radiologic follow-up (anteroposterior and transscapular). Visual Analog Scale for subjective evaluation of pain and function. Results: After 17 months, the average Constant Score was 66.8 points (87% of the age- and sex-related normal values). Implant-related complications (plate impingement, screw perforation into the glenohumeral joint, loosening of screws) occurred in nine cases (17%). The rate of avascular necrosis was low (5.5%) and no cases of nonunion were seen. Conclusions: The effectiveness of the NCB is similar to other published methods of treatment for fractures of the proximal humerus and potentially provides a less invasive option for this problem. Complication rates and functional outcome in this series are comparable to the literature. An important factor in this technique is the process of percutaneous fracture reduction. The NCB plate is suitable for both a minimally invasive technique or standard open reduction and internal fixation through a deltopectoral approach; the surgeon must decide which approach is best for each particular fracture pattern and should be comfortable with both techniques.